Electrophotographic imaging forming apparatus such as laser printers, utilizing the principle of electronic photography, which at least involve charging, exposing, developing, transferring, fixing, and cleaning processes to form images on the medium such as paper. The imaging forming apparatus usually use detachable developer cartridges to complete the above processes.
In the charging process, a photosensitive member, such as photosensitive drum, is uniformly charged with a given amount of charge by a corona discharge method or by using a charging roller. In the exposure process, the surface of the charged photosensitive member is selectively exposed. Due to the photosensitive characteristics of the photosensitive member, the charge of the exposed region disappears by grounding. Therefore, after exposure, an electrostatic latent image is formed on the surface of the photosensitive member through the distribution of charge which corresponds to the designed image. In the developing process, the developing device, such as the developing roller, transfers the developer, such as toner, to the electrostatic latent image region with the force, such as the electric force, to visualize the electrostatic latent image. In the transferring process, the transferring device, such as the transfer roller, transfers the developer of the electrostatic latent image on the photosensitive member surface to the imaging medium such as paper. In the fixing process, the image fixing device firmly fixes the developer onto the imaging medium. In the cleaning process, the cleaning device, such as the wiper blade, removes the residual developer from the surface of the photosensitive member to avoid printing defects in the next image forming cycle.
Conventional developer cartridges usually have a toner hopper unit and a waste bin unit. The toner hopper unit comprises a developing roller, a doctor blade, a toner adder roller and an agitating frame. The waste bin unit comprises a photosensitive drum, a charging roller and a wiper blade. Some developer cartridges only have a toner hopper unit, but do not have waste bin units. In the prior art, some developer cartridges are provided with chip contact mechanisms which are fixed on the cartridge body. The chip contact mechanism has a chip installation position and the chip is fixed on the chip installation position. When the developer cartridge is installed inside the printer, the chip on the developer cartridge is in contact with the contact inside the printer, the circuit is turned on, and the developer cartridge starts working. However, this method creates relatively high impact on the contact of the imaging forming apparatus which may damage the contact of the imaging forming apparatus, resulting in poor contacting and interference with the work of the developer cartridge.